Hey y'all. I was really glad to find this forum.
I'd like to get some feedback on plans I have for an el natural crayfish tank.
The tank is 20 gallons, long and low (30"x12"x12"), it's close to a south-facing window, it typically gets a ton of indirect sunlight and direct sunlight on parts of the tank for up to a few hours, especially in winter when the days are shorter (it gets almost no direct sunlight in the summer). I could move the tank, but I'd like to at least try keeping it where it is now.
The substrate is 1/4" peat moss, on the very bottom, then 1" potting soil, covered by 1/2" of sand from Lake Michigan (lots of shell fragments in the sand), and then 1/2 inch of mixed-size gravel from lake Michigan--mostly it is fairly fine, like coarser aquarium gravel.
My hope is that the crayfish won't be able to dig through the sand, because it's too fine for them to push or carry, and any tunnels they make in it will collapse. I have several large rocks (actually, mostly bricks and fragments of ceramic pots or roof tiles) that rest directly on the sand (beneath the level of the gravel), and a couple others that have only gravel and sand (no soil) under them, and are set up in such a way that the crayfish could tunnel under them without causing them to collapse (they are supported by larger rocks in some places).
plants:
4 big strands of hornwort,
4 strands of egeria najas,
Eurasian water milfoil (to be taken from a pond near here, or my other tank--not added yet)
1 water primrose
pretty small fragment of java fern from another tank
I also have planted some "betta bulbs":
1 some sort of aponogeton,
1 "water lily",
2 onions.
All the plants are anchored in the substrate, with large rocks inserted into the substrate around the "base" of the stem so the crayfish can't dig them up or dig under them. Of course, I can't stop the crayfish from clipping the stems with their pincers, I'm just hoping they won't do that (I've kept crayfish before, they never clipped stems).
animals I definitely want:
1-2 crayfish
3 mollies (from a friend who didn't have room in his tank--I may give them back to him if they crayfish bothers them too much)
pond snails
Malaysian trumpet snails (to turn the gravel and help mulm fall through to the sand)
other animals I'm considering:
8-12 white clouds
-or- 1 or 2 goldfish (need to research which ones don't get too big)
1 Siamese algae eater (not so much for algae control as because I have no place else to put him--they eat algae as juveniles but not as adults, or so I've heard)
So, what I'm wondering is, assuming the plants aren't dug up by the crayfish, will their roots draw enough nutrients out of the substrate to process the mulm that falls through the gravel? Most of the ones I have I think mainly draw nutrients from the water column, not the substrate, but if the roots extend far enough (milfoil roots seem to go pretty far) this might not be too big of an issue. Are there any plants you would recommend adding? I'm thinking something that will eventually become emergent, or else floating plants, maybe water hyacinth or salvinia, to overcome any lack of CO2 in the water.
This tank will get a lot of light, so I'm assuming algae will be a problem, unless my plants are really good at competing with it. I don't mind scraping algae off the sides every so often, but I'm afraid of green hair obscuring all the nice gravel and rocks and things.
Thanks in advance for any suggestions.
I'd like to get some feedback on plans I have for an el natural crayfish tank.
The tank is 20 gallons, long and low (30"x12"x12"), it's close to a south-facing window, it typically gets a ton of indirect sunlight and direct sunlight on parts of the tank for up to a few hours, especially in winter when the days are shorter (it gets almost no direct sunlight in the summer). I could move the tank, but I'd like to at least try keeping it where it is now.
The substrate is 1/4" peat moss, on the very bottom, then 1" potting soil, covered by 1/2" of sand from Lake Michigan (lots of shell fragments in the sand), and then 1/2 inch of mixed-size gravel from lake Michigan--mostly it is fairly fine, like coarser aquarium gravel.
My hope is that the crayfish won't be able to dig through the sand, because it's too fine for them to push or carry, and any tunnels they make in it will collapse. I have several large rocks (actually, mostly bricks and fragments of ceramic pots or roof tiles) that rest directly on the sand (beneath the level of the gravel), and a couple others that have only gravel and sand (no soil) under them, and are set up in such a way that the crayfish could tunnel under them without causing them to collapse (they are supported by larger rocks in some places).
plants:
4 big strands of hornwort,
4 strands of egeria najas,
Eurasian water milfoil (to be taken from a pond near here, or my other tank--not added yet)
1 water primrose
pretty small fragment of java fern from another tank
I also have planted some "betta bulbs":
1 some sort of aponogeton,
1 "water lily",
2 onions.
All the plants are anchored in the substrate, with large rocks inserted into the substrate around the "base" of the stem so the crayfish can't dig them up or dig under them. Of course, I can't stop the crayfish from clipping the stems with their pincers, I'm just hoping they won't do that (I've kept crayfish before, they never clipped stems).
animals I definitely want:
1-2 crayfish
3 mollies (from a friend who didn't have room in his tank--I may give them back to him if they crayfish bothers them too much)
pond snails
Malaysian trumpet snails (to turn the gravel and help mulm fall through to the sand)
other animals I'm considering:
8-12 white clouds
-or- 1 or 2 goldfish (need to research which ones don't get too big)
1 Siamese algae eater (not so much for algae control as because I have no place else to put him--they eat algae as juveniles but not as adults, or so I've heard)
So, what I'm wondering is, assuming the plants aren't dug up by the crayfish, will their roots draw enough nutrients out of the substrate to process the mulm that falls through the gravel? Most of the ones I have I think mainly draw nutrients from the water column, not the substrate, but if the roots extend far enough (milfoil roots seem to go pretty far) this might not be too big of an issue. Are there any plants you would recommend adding? I'm thinking something that will eventually become emergent, or else floating plants, maybe water hyacinth or salvinia, to overcome any lack of CO2 in the water.
This tank will get a lot of light, so I'm assuming algae will be a problem, unless my plants are really good at competing with it. I don't mind scraping algae off the sides every so often, but I'm afraid of green hair obscuring all the nice gravel and rocks and things.
Thanks in advance for any suggestions.